First lady Michelle Obama on Friday delivered a subtle rebuke to the presumptive Republican nominee seeking to succeed her husband — without mentioning Donald Trump by name.

Speaking at the City College of New York’s commencement ceremony on Friday, the first lady criticized Trump’s proposed wall and she lamented “name calling” of opponents and “folks out there” who “demonize and dehumanize entire groups of people.”

Obama urged the graduates to heed “the lessons of our history” and cherish immigrants’ contributions to America. She recounted alumni who went on to greatness.

The first lady specifically mentioned retired Gen. Colin Powell, the former U.S. secretary of state, and Jonas Salk, the virologist who developed and discovered the first polio vaccine.

“Here in America, we don’t give into our fears. We don’t build up walls to keep people out, because we know that our greatness has always depended on contributions from people who were born elsewhere but sought out this country,” she said in a 23-minute speech.

She referenced “some folks out there” who “view our diversity as a threat to be contained, rather than as a resource to be tapped. They tell us to be afraid of those who are different, to be suspicious of those with whom we disagree. They act as if name calling is an acceptable substitute for thoughtful debate, as if anger and intolerance should be our default state rather than the optimism and openness that have always been the engine of our progress.”

The first lady spoke on City College’s main campus in Upper Manhattan under cloudy skies and sporadic drizzle before more than 3,800 undergraduate and graduate students and their families.

More than half of those who earned degrees Friday are the first college graduates in their families.

“One of us!” a woman shouted as Michelle Obama received an honorary degree.

“Flotus, we love you!” a capped-and-gowned graduate shouted, using an acronym for first lady of the United States. “We love you, Michelle,” another woman said.

Obama was preceded by a succession of dignitaries, including Sen. Charles Schumer (D-N.Y.), who theatrically ripped up the stump speech he’s given for more than a decade about being dumped, because Obama was there. He said doing so was his “gift” to the Class of 2016.